... of solutions. Answers to Exercises 37(The last three equations come from the circuit involving i0-i1-i6, the circuit involving i0-i2-i4-i5 - i6, and the circuit with i0-i2-i3-i5-i6.) ... 50, 0, 20, 0, 30)results from choosing i4= 0.34 Linear Algebra, by Hefferon > A:=array( [[7,0 ,-7 ,0],[8,1 ,-5 ,2],[0,1 ,-3 ,0],[0,3 ,-6 ,-1 ]] );> u:=array([0,0,0,0]);> linsolve(A,u);prompts ... is the definition of nonsingular. (Another way to say the samething is to say that they fall into none of the above classes.)42 Linear Algebra, by Hefferon Two.I.1.44 (a) We outline the check...